Quilting has been done for thousands of years in many cultures worldwide. The earliest known record of a quilt is shown in Egyptian artwork dating back to about 3400 B.C. The oldest existing quilt was found in Mongolia and dates back to about 100 B.C. Quilted materials have found many uses over the centuries, such as padded undergarments worn by knights under their armor, winter jackets, art tapestry for wall and floor coverings, padded/protective covers, and most commonly as artistic and/or functional blankets.
Generally, quilting may be described as the joining together of two or more layers of material by sewing to make a thicker padded/insulating material. Typically, a quilt includes three main layers: a bottom layer (or backing material), a top layer (or quilt top), and a batting or insulating material layer sandwiched between the bottom layer and the top layer. Needle and thread sewing in various patterns ties the three main layers together. Quilting may be used to prevent the batting material (e.g., goose feathers, wool) from bunching or gathering at one end of a comforter, for example, to maintain or control the distribution of the batting material across the comforter. Typically, the sewing is done in artist patterns (e.g., geometric shapes and fanciful patterns and sequences). Sometimes, artistic embroidery is incorporated into the sewing. Sometimes such embroidery patterns are preformed in the top layer before joining the three main layers, and thus only seen on the top side. And sometimes, the embroidery patterns are performed during the process of joining together the three main layers such that the same sewing pattern can be seen on both sides.
Quilting can be done by hand (with or without the use of a quilting frame), using a sewing machine (with or without the use of a quilting frame), or using a specifically designed longarm quilting system, for example. Indeed, some modern, sophisticated longarm quilting systems include computer aided design (CAD) and/or computer motion control of the sewing needle to create highly complex patterns and embroidery artwork, as well as highly repeatable and precise patterns. Quilting methods can range from as simple as a single person with a needle and thread, to a group of people working together with needle and thread on different portions together, to a simple wood frame securing the fabric layers and hung from a ceiling, to eight to fourteen foot metal framed longarm quilting systems with manual movement of a sewing machine on horizontal-plane rollers, to computer aided and/or computer controlled longarm quilting systems (e.g., Statler Stitcher® by Gammill®), to mass production industrial quilting machines.
FIG. 1 shows a longarm quilting system 30. In a typical longarm quilting system 30, there are three or more rollers (e.g., rollers 31, 32, 33, 34). A first roller 31 retains a first end of a backing material (bottom layer) 35, a first end of a quilt top material (top layer) 36, and a first end of a batting material (padded/insulating middle layer) 38. As the quilt is formed from a first quilt end to a second quilt end, the first quilt end is rolled onto and retained on the first roller 31. A second roller 32 retains a second end of the backing material 35. At the beginning of the quilt formation, most of the backing material 35 is rolled onto and retained on the second roller 32. As the backing material 35 is rolled onto the first roller 31, the backing material 35 is unrolled from the second roller 32. In the example in FIG. 1, the backing material 35 is in an S-shaped scroll configuration. A third roller 33 retains a second end of the quilt top material 36. At the beginning for the quilt formation, most of the quilt top material 36 is rolled onto and retained on the third roller 33. As the quilt top material 36 is rolled onto the first roller 31, the quilt top material 36 is unrolled from the third roller 33. The longarm quilting system 30 of FIG. 1 includes a fourth roller 34. The fourth roller 34 may be used to retain a second end of the batting material 38. At the beginning of the quilt formation, most of the batting material 38 is rolled onto and retained on the fourth roller 34. As the batting material 38 is rolled onto the first roller 31, the batting material 38 is unrolled from the fourth roller 34. The fourth roller may simply be a bar extending across the quilt frame (not pivotable) in some longarm quilting systems.
For the exemplary longarm quilting system 30 shown in FIG. 1, the workspace 40 where the sewing is done is located between the first and second rollers 31, 32. The sewing machine portion 42 of the system 30 has a long arm 44 that extends over the first roller 31 to allow for clearance of the rolled up material on the first roller 31. For a large workpiece 46, such as a queen-bed-size workpiece, when nearly completed and most of the workpiece 46 is rolled onto the first roller 31, the size of the rolled material may become quite large, which is why the sewing machine 42 has a large generally C-shaped structure extending about the first roller 31 to provide clearance for the material rolled onto the first roller 31.
Still referring to FIG. 1, at the workspace 40 where the sewing is done, the workpiece 46 is suspended between the rollers 31 and 32. During a preferred use of the system 30, the rollers are locked into their respective positions such that the workpiece 46 is suspended between the rollers without much, if any, sagging. Preferably, the rollers should be locked such that the workpiece 46 is within an optimal range of suspension tension; so that the workpiece 46 is not stretched too tightly in a way that would distort the Y-direction shape while also not being too loose in a way that would allow too much sagging of the workpiece 46 at the workspace 40. A reference Cartesian coordinate system orientation is shown in FIG. 1. The rollers typically provide sufficient tension in the Y direction to prevent too much sagging. But in the X direction, there is need for support, especially when the workpiece 46 is large and/or heavy (which may be dependent on the thickness and composition of the materials used for the various layers).
As shown in FIGS. 1 and 2, a current practice is the use of clamps 50 and straps 52 to provide an X-direction tension on the workpiece 46. As with the suspension tension discussed above for the Y direction, it is desired to retain the workpiece 46 within an optimal range of suspension tension in the X direction so that the workpiece 46 is not stretched too tightly in a way that would distort the X-direction shape while also not being too loose in a way that would allow too much sagging of the workpiece 46 (especially at the lateral edges not supported by the rollers).
In FIG. 1, the system utilizes four clamps 50. There may be any number of clamps used (including none at all) when using a longarm quilting system 30. Generally, the larger the quilting frame 54, the wider the workpiece 46, and/or the larger the distance between the rollers 31 and 32 (i.e., the larger the workspace 40 for sewing), the more clamps 50 are desired or needed, especially while sewing at or near the lateral edges. Next, the use and disadvantages of this clamp and strap configuration shown in FIGS. 1 and 2 will be described.
The clamps 50 of FIG. 1 are shown attached to the lateral edges of the workpiece 40. A strap 52 is attached to the handle of each clamp 50, and extends from the clamp handle to the quilt frame 54. Most currently used straps 52 include a hook-and-loop type fastener material (also commonly known by the trademark Velcro). Strips or pieces 56 of hook/loop fastener material are attached to the quilt frame 54. Hook/loop fastener material on the strap 52 is adapted for engaging with and sticking to the hook/loop fastener material 56 on the quilting frame 54.
FIG. 2 is a closer view of one clamp and strap configuration of FIG. 1. The clamp 50 of FIG. 2 is a clamp type that is supplied with or as an accessory for some longarm quilting systems 30. The clamp 50 of FIG. 2 is a squeeze type clamp made from metal, with a heavy spring 58 and silicon covered tips 60. A strap 52 is bolted to the handle 62 of the clamp 50.
Now, usage of the clamp and strap configuration shown in FIGS. 1 and 2 will be described. After arranging the quilting materials 35, 36, and 38 with a desired Y-direction tension using the rollers 31, 32, 33, and 34 (as described above), one of the clamps 50 is attached to the lateral edge of the workpiece 46 (typically the backing material 35), as shown in FIG. 2. There may be a preferred order of placement, but generally the order of placement of four clamps 50 shown in FIG. 1 is not critical to usage (i.e., selecting which of the four clamps 50 to position first). The user then extends the strap 52 from the clamp 50 towards the quilting frame 54 generally along the X direction. The strap 52 is pulled gently by the user to apply a desired amount of lateral (X-direction) tension on the workpiece 46 (to reduce or avoid sagging). Then the user engages the hook/loop fastener of the strap 52 with the loop/hook fastener strip or piece 56 on the quilting frame 54 while maintaining the desired tension on the strap 52. The hook and loop fastener formed thereby is then used to retain the position and tension on the strap 52, which is translated to the workpiece 46 via the clamp 50.
When the user desires or needs to move the workpiece 46 to change the portion of the workpiece 46 located in the workspace 40 (e.g., to roll the completed or partially completed workpiece portion on the first roller 31 from the workspace 40), the clamps 50 are typically removed first before rolling the materials. Typical usage of the clamp and strap configuration shown in FIGS. 1 and 2, may include the following steps for removal. The user disengages the hook-and-loop fastener for a selected strap 52 (by pulling the strap 52 away from the quilt frame 54). Then, the user squeezes the clamp 50 to release its grip on the workpiece 46 and removes the clamp 50 from the workpiece 46. Alternatively, the clamp 50 may be removed while leaving the straps 52 in place attached to the quilt frame 54 by the hook-and-loop fastener. Or, the strap 52 may be removed or repositioned after removing the clamp 50.
Now at this point during use of the clamp and strap configuration of FIGS. 1 and 2, disadvantages and discomforts of using this configuration reveal themselves. If the clamp spring 58 has a relatively large spring constant for a given user, the user may need to use two hands to squeeze and remove the clamp 50. The majority of quilters are women, and of them, the majority of them are over fifty years old. Thus, a clamp 50 that requires a woman to use two hands to squeeze it is undesirable to many users. At this point, the strap 52 is probably dragging on the floor. Also, when the strap 52 was engaged on the quilting frame 54, an end of it may extend to the floor as well (such as when a workpiece 46 is wide relative to the quilting frame 54), as shown in FIG. 1. A hook/loop fastener has a tendency to grab and retain dust, fabric fuzz (especially batting material), hair, rug material, carpet material, food particles, debris, and other loose materials typically found on a floor. As a result of the hook/loop fastener regularly touching the floor during use, the strap 52 and/or the hook/loop material 56 on the quilting frame 54, tends to become not only less visually attractive (sometimes downright gross over time), but also less functional. The strength of a hook-and-loop fastener when engaged greatly depends on the hook-and-loop fastener being free from debris that can obstruct a hook from engaging a loop to form the fastener. Many users strive to keep their hook-and-loop fasteners clean by trying to prevent the strap 52 from touching the floor. For example, some users try to hold the strap 52 with one hand while manipulating the clamp 50 with the other hand (one-handed clamp operation), but some users are unable to do this due to strength and/or coordination limitations. For example, some users try to roll up or ball up the strap 52 before releasing the clamp 50 and securing the roll/ball of strap with a rubber band. This is very time consuming and annoying to many users. Some users tend to replace the straps or the entire clamp and strap combination regularly because the straps become dirty, unsightly, and/or non-functional, which can become expensive over time.
Another issue is where to put the clamp 50 after removing it from the workpiece 46. Some users clamp it to the quilting frame 54, but many quilting frames are not conducive to allowing the clamp to be attached (e.g., when the quilting frame is larger than the maximum bit opening size of the clamp). Many user do not bother with winding up the strap 52 (to keep it from touching the floor) and use the hook-and-loop fastener on the strap 52 to attach the clamp 50 to the quilting frame out of the way. This leads to a large portion of the strap 52 laying on the floor to collect debris. Furthermore, a strap 52 hanging down onto the floor during use can create a trip hazard, such as when one end of the quilting frame is at or close to a walkway or doorway. Few users have enough extra space in their studio to prevent an end of the quilting frame from being at or near a walkway or doorway. Hence, the use of straps that rely on hook-on-loop fasteners may have many disadvantages that are undesirable to many users.
One of the disadvantages of heavy clamps (e.g., those made from metal and those that are large) is that the weight of the clamp itself may induce sagging of the workpiece 46, which is typically undesirable. A disadvantage for some clamps, in the viewpoint of some quilters, is that the clamp is too hard to squeeze for the typical quilter or too complicated to lock and unlock, thereby requiring two hands to operate the clamp itself A disadvantage of some clamps is that they are too bulky or too large in the Z direction relative to the X-Y plane. For example, the clamp 50 shown in FIGS. 1 and 2 is particularly large in the Z direction relative to other possible clamp options. This can cause problems for the user when trying to sew at or near the lateral edge because the sewing machine can bump or hit the clamp 50 causing the workpiece to move and/or the clamp 50 can prevent the sewing head 64 from reaching the full extent in the X direction desired or needed during sewing. Often the bottom of the sewing machine 42 will collide with the bottom of the clamp 50 without the user seeing the forthcoming collision because the larger bottom portion of the sewing machine is not visible under the backing material 35 during use (see e.g., FIG. 2). Such collisions can cause an intended sewing path to be hindered and altered, often requiring the user to stop, remove threads, and reset the sewing head (which may be very difficult and time consuming, as well as frustrating and discouraging). Many times the backing material layer 35 is not selected to be sufficiently wider than the quilt top layer 36 to allow for enough space and clearance of a large and bulky clamp 50. Often customers send to quilters a partially completed quilt (e.g., designs and patterns stitched, embroidered, or formed in a quilt top but not yet formed with the other layers to make a quilt) which does not have a large enough backing material layer because they do not have experience or knowledge of the need for larger backing material for longarm quilting systems. Hence, in the opinion of many users, there are many disadvantages and undesirable aspects of currently available clamps and clamp/strap combinations for use with quilting frames and/or longarm quilting systems.